Rebooting CUCM Pub and Sub

[Dustin Peet]

I'm going to be rebooting my CUCM this weekend.  This will be my first time and I've read the article https://supportforums.cisco.com/docs/DOC-4870.

I understand rebooting the Pub, let it come all the way back up, and then reboot the Sub.  My only question is if there are any general gotchas or things to look out for.  I'm just trying to absorb as much info as possible and get my ducks-in-a-row before I do this.

Thought this would be a good place to get some general, possibly "non-offical", but still great advise.

Thanks all

[Nadeem Ahmed]

The docs is perfect, apart from that you can check the database status and alarm if any RTMT tool . CLI you can use to check database .

Br,

Nadeem Ahmed

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[Chris Deren]

In addition to great answer by Nadeem (+5), things I normally take a note of before and after for comparison:

phone registration snapshot

media resource registration

then it is always to do some baseline testing to ensure things came up properly, i.e. outbound and inbound PSTN call, call to any integrated applications: voicemail, contact center, etc.

HTH,

Chris

[Nadeem Ahmed]

Thanks Chris Hi5 for you for adding additional information to this thread to complete it.

Br,

Nadeem

[Dustin Peet]

Thanks guys.

Quick question.  In cli to check the db would you just use "utils dbreplication status"?

The baseline testing is something I planned on doing as well but the snapshot of phone and media registration was a great.

[Nadeem Ahmed]

You can check with command below

show perf query class "Number of Replicates Created and State of Replication".

Below is very good doc explained on how to verify db_replication and status of each of value comes in.

https://supportforums.cisco.com/docs/DOC-13672

HTH

Br,

Nadeem

Please rate all useful post

[Dustin Peet]

Great doc. I'll definitely read it.

Two other questions that I've thought of.  I rebooted CUC a few months back and I remember that it took around 15 minutes for all services to be restored.  Is CUCM similiar in timing?

Also I thought that in our config if the sub went down the phones would register to the pub.  Does that sound right, or when I take down the sub should I expect all phones to be down/unregistered?  If so, when the sub comes back up how do I make then re-register with the sub?

[Chris Deren]

Yes, depending on type of a server it will take several minutes for all services to be restored.

Your redundancy is driven by CUCM Group configuration, if both servers are listed in the group then all devices will register with the second server when primary goes down.

HTH,

Chris

[Nadeem Ahmed]

its purely depend on servers types.

Coming to next question,Yes it will fallback to PUBLISHER if you have configured CM_GROUP in such a way ie redundancy

SUB (Priority 0)

PUB (Priority 1)..

So when SUB comes back again,there is KEEPALIVE mechanisim run to check the connecitivty between Phones and CUCM. when phones finds SUB is up through KEEPALIVE and then again it re-register back to SUB.

Br,

Nadeem

Please rate all useful post.

[Dustin Peet]

Looks like they are both listed in the group and I assume order is important as sub is listed first and pub second.  Working under that assumption, I am in the config of Sub(Priority 0) and Pub (Priority 1). 

[Nadeem Ahmed]

That's Correct. SUB is in first priority and PUB second.

Br,

Nadeem

Please rate all useful post.

[Dustin Peet]

This is all starting to come together now.  Thank you both for you input!

Just to wrap it up:

First I'll reboot the Pub.  I'll run either a cli command or report/RTMT to view replication status and wait until replication status is a 2. Once db replication is in order then I'll take down the Sub.  At that point the phones (in my config) will failover/register with the Pub.  I'll begin checking db replication again.  Once that is back to a 2 then check phones and wait until they re-register with my Sub.  Then I can begin to make test calls in/out the sip trunks and test calls to CUC.

Does that sound about right?  Am I over simplifiying anything?

[Nadeem Ahmed · Accepted solution]

just add in best practise as Chris said take note of Phones Registration Snapshot and Media Resources.

Perfect and you are good to go :-)

Br,

Nadeem

[Chris Deren]

Plan is correct.

Chris

[Dustin Peet]

Awesome.  Thank you both again so much!!